No I will be up in the mountains for a couple of weeks. I need to make up cables, and it will be a good test bed to learn how to measure distortion on my setup.
So I finally got around to powering mine up and having an issue. I had no power past the meanwell power module so I removed the 2 inductors and have a dead short on the positive side. I looked everything over pretty carefully with an inspection scope and can see no shorts or solder balls , any recommendations? Unfortunately I machined my case for it so if I can fix I will probably have to buy a populated one.
Bill
Bill
A dead short on positive rail can only come from a solder bridge or a bad component like a failed cap. Remove the small X7R C15 and C17 rail caps, and check polarity on the electrolytic input cap. Also check polarity of the power supply input to the DCDC. Please take some high res photos front and back and post them here and we will debug. It’s a very straightforward circuit and the PSU should be simple. We will fix it - don’t worry.
Is your +12v input same as photo (positive towards the front of the board)?
Is your +12v input same as photo (positive towards the front of the board)?
The polarity in is correct, the cap orientation is correct. I removed c17 and checked it. I will reflow all the cap pos to ground and send you some pictures. Any chance you can give me the pictures of the mask to help tracing.
Thanks for your prompt response ,
Bill
Thanks for your prompt response ,
Bill
Looks like you figured it out but here are the paste/mask/silk gerber files in case you still need it.
Very nice work on your amp - what Class D amp is that?
Very nice work on your amp - what Class D amp is that?
It is the 300W one offered by Eric in the market forum. I have bought 4 or 5 of them and gifted them to people. Way cheaper than most stuff I build and they can’t tell the difference. Thanks for the assistance it means a lot to me.
Bill
Bill
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So I do have a 15+/- power from the amp however when I measured it it was 14.7+ and 15.3- would it be better to keep the meanwell power supply and run it off just the single +14 V or is that to much voltage for it?
Thanks
Bill
Thanks
Bill
I think you need to use a 7812 to drop the 14v or 14.7v to 12v before feeding the DCDC converter. It might work but not sure about longevity. Check the datasheet for the DCC converter and look for absolute max rating. In a car for example, “12v” is actually 13.7v since batteries typically make that when fully charged.
Spec sheet showed it good up to 18v, it runs cool. Voltage output is much more accurate than voltage from amp module. The input boards effects the sound of the amp module more than I expected. It brings in more mid to high frequency resolution, makes the amp brighter. Makes me more aware when you are designing an amp you have to look at them as a complete system, and randomly making changes may not be optimal. We will see after everything breaks in, I can always eq it if it is to bright. I was also surprised how much more the imaging improved.
Bill
Bill